Automatic disconnecting pot head



July 26, 1927. 1.637,090

A. C. RUMBLE AUTOMATI C DISCONNECTING POTHEAD Filed Nov. 5. 1926 Ig f 217 19 fi; o I 37 1r l 1 iff" f 6 Patented July 26, 1927.

UNITED STATES PATENT OFFICE.

ALEX c. RUMBLE, .or Los ANGELES, CALIFORNIA, AssI'GNoR or ONE-HALF "roWILLIAM EDWARD LA UEB, oF Los ANGELES, .CALIFORNIA Appuc'altie'n meaNgember 5, 1926, "'seria1 No.146,374.l

tween the underground cablesf-andnthefcables ""tlle'l';

or conductors that vextend upwardly lamp supporting'"post 'or standar.''in the event tliat'jtheilatter shoullflie accidentally?" View, myinvention consists in certain novel features of construction andarrangement of parts'thatfwill hereinafter be more fully deyscribedandclaimed andI illustrated in the :accompanying drawing, in 4which-VllF1001 '1s 'a vertical'section Itaken on a 'cene taken on 4the \i's"'a`=fdetail 'elevational vieur of a to 'generally 'improvelupon:andfsirfplifyll the', i

.and further, to provide :1.devie'f the char-f act-er referred to thatisrelatively'siinple in construction', inexpensive' ofvv manufacture '1-and which inay be readilyiassembled and n stalled for use. Y

It' will be understood that{liscpnpectingif pot-heads of the type towhichIiiyinveiition'f 'Suitable nortcorrodlble material, relates aregcnerallyused'i'nthe base pori coppefandsald'slell or housing tions otthe lamp' supporting .posts vand standards thatforni a' part of streetlighting# systems and, in viewof Athe'A fa'ict'that the* lainp posts orstandards 4are"sonxetirnes struck and over-'turnedor'broken, it'ishigh-f" ly desirable and in some instances'obligatory1 that theconnection between the underground j cables andconductois that leadupwardly through the posts or standards he of such nature that an'autor'iatic disconnection he effected in the event that the post orstandard is broken or over-turned and at the. saine time that theundergrouiul cables vbe shrt-- circuited within thi` hase ofthe'postsor' standards.

It is therefore one of the principal objects Of myinvention to provider.disconnecting'v pot-headl that may he readily installed in the lampcarrying posts and standards of' street lighting systems andthe like'and which pot-head will act automatically in the event. that the postor standard is overturned or broken, to instanl)Y effect a dis'connection ot the partsthat conduct'the curirent to the lamps of thepost oij'standardv and parts of which pot-head are effective inshort-,circuiting the underground cables', thereby eliminating a source'of danger that would otherwise exist` liy'reason 'of an open: circuit inthe lighting eircuit.

lith the foregoing anduother objects inl Aexisting forms 'ofdisconnectingpot-heads; fFi'g. 5*,is in elevatonal-'view of a modifiedform' of :the: automatically acting disconnectmg means Referring byVnumerals to thc .accompany- 'ing drawing which illustrates a practicalemf-bodiment' Iof f my invention,- 10 designatesVv the '-bdy'ofa' shellor housing that isformed of preferably eing sub- Stantially'oval-Shpedin horizontal section. The-,bottom *of the housing is provided -\vi thspaced openings '11 4'for the' reception 'of the end portions of 'a pairoflu'nder-ground-cables` 12.*;Surrounding the openings 11 aredepending'lange's 13 'and 'the-Jewel' portions oftlie" Alatt'er'arefirmly clamped' tolthecables12. "I

A cap Aor 'cover 14 is removably seated on the upperfend of the body olthe shell or housing-"10 and in order to retain said cap or cover 0n thehousing, portions of the'eud walls-.of said coverare pressed outwardlyas designated by 15 in'order to receive oorresponding projectingportions 16 that are pressed out\ \'ardly'=in the end portions of thehousing 10, it being'undeifstood' that the portions ljoceupy theoutwardly pressed port-ions'15 Lwhenthe cover is properly positioned ontli'e housing. The top ot' cover 14 is provided with spaced openings 17,which accommodate the cables 18 that extend upwardly in the lamp post orstandard and surrounding these openings 17-'are upwardly projectingflangesl) that are firmly clamped tothecables 18.

" 'Removably positioned at an intermediate point Within the housing 10is av horizontally 'disposed partition 2O of'suitab'le insulating.n'laterial7 preferablv fiber. and whichp'a'rtition is retained inposition bythe engagei l' l -`I1 l l inentiof its end portions ingroovcs'or indentations 21 that are formed in the end por tions of thewall of housing 10.

Extending through the partition 20 and in vertical alignment withthe-cables 12 are the lower portions 22 of socket members 23 and thelower portions 22 of said' socket members are externally threaded` forthe reception of upper and lower clamping nuts 24 and 25 respectively.

The upper clamping nuts, when4 tightened` engage against the underfaceof partition 20, thereby securely clamping the sockets to saidpartition. The lower portion of each socket 22 is. provided with anv-axially disposed bore or recess 2G that is internally threaded lil)-and said lower portion 22 is provided with a centrally arrangedlongitudinally dis` posed .slot 27. The threaded. bore 26 receives theend portion of the conductor 28 that passes through cable-,12: andwhen.the lower one of the nuts 25 on the lower portion of the socket memberis screwed downwardly on said lower portion, the divided parts of thesplit lower portion 22 are clamped upon` the conductor 28,50 that.thezlatter is.

very lirmly secured to the socketimeinber.

The upperportion 230i each socketmein, ber pro]ects upwardly. into thechamberV within the housingrabove the .partition- 20 and said upperportion i s pr0vid ed.-,witl1 an vaxially disposed bore or recess.29.3thatl re.

ceivesv thelongitudinal-ly slotted lower portion.30of.a contact plug 31.The upper. portion of the body of this .plugl is externally threaded.for thereceptionof aclafmping nut` 32 .and saidrupper portionyis also;provided .with an axially disposed threaded: boixeor, recess 33- thatreceivestheendfportion: of, the conductor 34' and which latter.-projects' from the end of the corresponding cahle 18.-

The upper portion of eachpl-ug 31. is pro! vided with a centrallyarranged, longitudinally disposed slot 35fand thus Vwhengnut 32 isscrewed. .upwardlyon .the threaded por-v tion of the plug, the split,endthereof will very securely clamp the'engagedA end of conductor 34 sothat said. plug isjpractically locked to the conductor. Y

Arranged within the chamber in housing 10 above the partition 2O,therein and .im-.v

Ving members 37 and 38 are perforated at the proper point for theaccommodation of` cables 18.

Secured. in any suitable manner to the upper surface of partition 2O arethe hase portions 39 of short-circuiling inenilicrs` said base portionsbeing in direct contact with the intermediate portions of the socia-tinein bers and the inner ends of the base portions 394areextendedupwa-idly to forni springv contact fingers 4,0. Secured in aniYsuitable manner to the central portion ot' thi` top 14 a'nd ,extendingdownwardly therefrom is a pin or finger 41 of suitable insulatingniaterial, either hard rulilier or liber. and when cover 14 is properlypositioned on the lionsing, the lower portion of this insulating pin orfinger occupies a, position between thc upper portions of the contar:lingers 1'() and holds the saine out of Contact with other.

Positioned on top of the contact lingers 40 is a disl: 4i) of suitableinsulatingl inaterial through the center ol which projects each thelower portion of thc linger ll and inter- A posed between this disleandthe set-tion 2li ol' insulating material is :rn expansive coil spring 43that surrounds the stein or linger 41. Under normal conditions. or whilecap 144 is positioned on thc housing. spring 13 iscompressed and undertension, but, as the cover is clamped to the cables 1S and thc itternormally occupy fixed positions within the post or standard, the spring4:) will be retained under compression as long as the cover occupies itsnormal position on the housing 10.

The entire space in the housingY l() beneath the insulation partition 2Ois lillcd with a suitable insulating compound.

Thus, when my improved pot-head propverly assembled a'nd applied foruse, it will be seen Athat the terminal portions ot' liec undergroundAcables are in direct alignment With and are directly connected to theter- ,minal portions of the cables 18 that extend upwardly into the lamppost or standard and that the conductors and connections on one lside'of the circuit are thoroughly insulated I pot-head isassocizrted isstruck and over turned,. the cables 18 will, as the post or Standardswings downwardly, exert an upward p ull on the parts of the pot-head towhich said cables a're connected and which parts include the cover 14and the Contact plugs 31 and, as this upward pull continues, VtheCoverwill be drawn from the housing l0 and the split lower portions 30ot the contact plugs will be withdrawn from the recesses 29 in the upperportions of the sockets 23 land this disconnecting movement is greatlyaccelerated and made positive by the action ot vcoilspring 43, whichexerts an upward pressure on the cover of the pot-head si'niifltaneouswith the'upward pulling inoreinent exerted .by the cables =,8. i

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i -Thuswith the existence of the power I storedl in the coil'spring43, adisconnection ofthe automatically acting contact springs- Y that arenormally held apart b the stem or Offinger 41- and in this constructionthe lower portion of the stem or finger is provided on its oppositefaceswith recesses 50 that receive correspondingly shaped portions of the ispring .fingers and which construction is effectivc in gripping the stemor -fingerfso as I'to prevent withdrawal thereof and consequently firmlyholding the cover in position non the housing ofthe pot-head. In thiscon- :struction thellow'er; portions, of the spring 2&0 fingers areextended toward each other be- A lo-wthe-llowerfend of the.finger41.sothat f i. saidi portions will make direct contact with` each otheiaassoon as theinsulatingtfingerA alias been withdrawniq'A Y an externallyar@ e; f ln Fig. 5, Iy have shown rangedfbow spring 51 thattakes theplace of I the coil spring 43fi`n exerting. upwardpressure-on the cover'when-thepot-head is dis-'.

"lf vf.f.connected as a result ofthe accidental over- 40;turning1;of;the lamp-supportingy post orl lstandard andiin this modified-structure,one end ofthe spring- 4is connected to the housing.ofthe,pot-headiavhile the other end termi- -ifnates inia -liookthatengages a ring 53 on i,

15 the top of Coverlet;

f; Amongtheiexceptional advantages of my improved.construction `ofpot-head are the 'tfoi'i'nation-of thei Shell orhousing: ofnonfzfcorrodible and non-breakablematerial and 59fwliich provisionenables the pot-,head to be .,fniadeg relatively i small andcomparatively lightinpweight and therefore capable of be-,ifingfsustaiiied within a single-lighting post without supports otherthan thecables that enter andextend through the post. Y

i The'housin'g ofthe pot-head is constructed so that the use of allscrews is eliminated; likewise there is no requirement for the sweatingon of lugs or the taping of joints 60 and there are no cork closedapertures through which filling compound might leak.

The socket members and Contact plug members are firmly clamped to theparts of the housing without the use of screws and 55 said sockets andplug members are arranged in f'direct alignment with each other so'thatdirect and straight or axially disposed connections are made between thecables that come from the underground conduits to the cables or conduitsthat pass upwardly into the post. Further, the use of a disconnectingpot-head of my improved construction enables the direct splicing of thelead sheathed cables that are brought into the lower portions of lampposts and standards to the rubber covered cables that carry the currentupward through the posts to the lamps supported thereby.

Thus it will be seen that I have provided a disconnecting pot-head thatis especially designed foi' service between the terminals of undergroundcurrent carr ing cables and the cables that extend upwardy into a streetlighting fixture, such as a lamp carrying post or standard, whichpot-head will be effective in instantly effecting a disconnectionbetween the current carrying conductors in the event that the lightingfixture is struck and overturned and the construction of said pot-headbeing such that it may be readilyassembled and applied for use. v

It will be understood that minor changes in thev size, form andconstruction of the VVarious parts of my improved automaticdisconnecting pot-headI may be madev and sub-,l stitutedvfor thoseherein shown and described without departing from the spirit of myinvention, the scope of which is set forth in the appended claims. I Iclaim as my invention:

1.- In a disconnecting pothead, a housing `formed in ,two parts,'each ofwhich is adapted toxrecei've a pair of cables, means within the potfheadfor detachably connecting the terminals-of the conductors in saidcablesand. means associated with4 said pot vhead fornormally exertingpressure onthe parts thereof tending to separate the saine and effect aydisconnection of theparts that connect the conductors within saidcables.

2. In a disconnecting pot-head, a housing, a cover tliere'forsaidhousing and cover be- .ingp'rovided with openings for the acceuimodationof cables, socket members secured to the conductors of the cablesentering the housing, contact plugs secured to the cables enteringthecover, which contact plugs are adapted to berreinovably positionediii the socketmembers wheiithe cover is properly positionedon thehousing and a spring ei .7,3 gaging said cover and normally tending toremove the same from said housing.

In a disconnecting pot-head, a housing, a cover therefor.y said housingand cover being provided with openings for the accommodation of cables,socket members secured to the conductors of the cables entering thehousing, contact plugs secured to the cables entering the cover, whichcontact plugs are adapted to be removably positioned in the lill) LIU'connected to the socket members therein amd means carried by the coverfor normally hold-ing saiid contact members out of engagement with eachother.

4. In a disconnect-ing pot-head, a. housing, a cover therefor, saidhousing and co-ver being` provided with openings for the reception ofelectric cables, socket members secured to the conductors ol one pair ofthe cables. contact plugs secured to the conductors of the other pair ofcaf-bles` which plugs are engage-d i-n the socket members when thecoverI is properly positioned on the housing and yielkliin-g pressuremeans bearing on the cover. and norma lflv tending to force the. samefrom` said honsi-ng.

5. ln a disconnecting pot-head, a housing, :r cover therefor` saidhousing and cover being provided withopenings for the recepti'on ot'elect-ricY cables. socket members secured to the conduct-ors of .onepair of the cables, lcont-act plugs securedI tov the confv duc-tors ofthe. other pair ot' cables. which plugs are engaged in the, 'socketlmembers when 'che vcover is properly positioned on the housing,yielding pressure means bearing on the cover and' noi-mall;Y tending toforce the. saine from said housing andlmeans with-L E in the'housing forsl'iort-eir'cniitmgthe con' ductors tha-t 'enter said housing when theacover is removed. l

G. In a disconnecting'pot-head, a housing, a cover therefor', .sa-id'housingl and 'cover be-l ing pi-ovicledwvith openings ffor `the,reception of pairs of electric cablesha pair 'of socket members 'withinthe housing to-Which the; conductors of a pairi of the cables areconnected, means for securing said sockety members Within'the housing,Contact plugs secured to the conductors of the cables that enter thecover, Whiclr plugs are adapted?! to engage theA socket members andmeans for securing said' Contact plugs to the'cond-uctors of the cablesthat enter Said cover.

T. In a disconnecting pot-heacha housing',I

secured to the conductors of the cables tha'tv enter the co-ver, whichIplugs are adapted to engage the socket members, means for securing saidcon-tact plugs to the conductors of the cables that enter Said cover anda spring hearing on said cover and normally tending to remove: the swinefrom said housing.

b. l-n a disconnecting pot-head, a housing,` a cover therefor` saidhousing and cover beimg pifovided with openings for the reception otpairs of electric cables, -a pair ot socket mem-bers within the.housingto which the conductors of a pair ot' the cables are connected,means 'tior securing said Socket members n'iihin the housing. conta/ctplugs secured io (he conductors ot the cables that. 'enter the cover`wvl'iiich pliugs. are adapted to engage the. socket members, means liorsecuring sxvid' contact phrgs tothe conductors oili- .the cables thatenter said cover, shortciil'cuitingmem-bers arranged within the housinga nd connecting saidl socket mem-bers andv means carried by the coverfor normally 'holdirngfsaiid short-cifreuiiting members out of4cor-itact with' each other;

In a disconnecting pot-head;T a two-part housing formeel ofnon-corroclible, non-breakable'rnateriail. each part of the housingbeing adapted tmreceive a pair of caibles, read-ily detachable 'meanswithin the housiang for connecting- 1the conductors Within sa'iid cablesand means associated! with sa-icl housing for normally-*exertingpressure on one of the parts thereof lendingl to: remove said partairdef'ect a disconnection of the parts that v'connect the conductors otthe cables.

1Q. In a disconnecting pot-head. a two- --fpart housingt'orined ofnon-corrodible, nonvbiealloilile material, each part of the housingbeings;1 adfaptecll toreceive the terminal portions of ai pair ofcables, socket members detaohalb'ly seated in one part of the housingandi connected' to the conductors of the. cables 'that enter said part,a pair of Contact members carried by the other part of the hous-Iing'and 4conncctecl'to t'he conductors in the cables that enter saidother part, which contact members are adapted to engage in the socketmembers and1 means associatedi with the two-part housing for normallyexertingpressure on one part thereof, which pressure tends to separatesaid Iparts and effect a disconnection ot' the contact members from saidsocket. members.

In testimony whereof I affix my signature.

ALEX C. RUMBLE.

